Alternating-current pole-changer circuit.



PATENT-ED NOV. 13, 1906.

7 B. H. SMYTHE. ALTERNATING CURRENT POLE CHANGER CIRCUIT.

APPLICATION FILED I'EB.1. 1906.

L'Q'ifneqsea 71474. M

UNITED STATES PATENT orrron.

EDWIN H. SMYTHE, OF CHICAGO, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ALTERNATlNG-CURRENT POLE-CHANGER CIRCUIT;

No. 835,870. I

Specification of Letters Patent.

Patented. Nov. 13, 1906.

Application filed February 1. 1996. Serial No. 298,917-

nois, have invented a certain newand useful Improvement in Alternating-Current Pole- Changer Circuits, of which the following is a full, clear, concise, and exact description.

My invention relates to an electric converter, and has for its object to provide an improved and efficient arrangement of circuits and apparatus for transforming alternating current into pulsating current.

7 Generally speaking, my invention contemplates an electromagnet adapted to operate mechanism, such as a vibratory pole-changer, for separating alternating current from a suitable source into positive or negative pulsations. The electromagnet is preferably polarized and included in the circuit leading from said alternating-current source, and switching mechanism is provided adapted to a ply pulsations of either character develope by said pole-changer to a desired circuit, said mechanism being also adapted when operated to automatically close said alternating-current circuit through said magnet.

A feature of my invention consists in the provision of means, such as a condenser,- in said alternating-current circuit for maintaining the pole-changer in tune with the alternating current, the condenser acting as ma synchronizer.

Another feature of my invention consists in its special adaptability for use in connection with telephone exchanges where the converter may be used to signal party-lines. I have found that by means of my invention a'great saving may be made in the installation and equipment of private exchanges from which party-lines radiate, since the converter may be located at the private exchange, and but a single wire, need be run from the main exchange for ringing purposesthat is, the one leading from the alternating-current generator-instead of the three heretofore necessary. The use of elaborate equipment at the private exchange is thus avoided.

I will describe my invention particularly by reference to the accompanying drawing,

which is a diagram illustrative of one embodyment of my invention.

The accompanying drawing illustrates my invention as applied to telephone-exchanges.

A party telephone-line A is shown extending in two limbs 1 2 from four substations I II III IV to a spring-jack terminal a at theprivate exchange or central .ofiice. The substation equipment is of the usual type, each limb having two ground branches from two substations containing signal-bells responsive to positive or negative pulsations of current, respectively,'the bells of stations I and II be- 'ing in ground branches leading from limb 1,

while the bells of the remaining stations III IV being in ound branches leading from limb 2. The ranches may be controlled by normally open contacts of relays as in bridges of the line at the different substations in the usual manner.

A plug 1), with a portion of its circuit, is shown at the rivate exchange for making connection with the line through the medium of spring-jack a. plug-circuit lead through the levers and normal resting contacts of keys 0 c c 0 respectively, which are adapted when operated to ground one conductor of the lug-circuit and apply pulsating current to t e other. The conductors 3 4 also lead through levers and contacts of a key 0, adapted to apply alternating current to the plug-circuit.

A grounded generator G is located at th main exchange or central Office, and a conductor 5 extends therefrom to. a private exchange, where it is connected by conductors 6 6 6 6 to extra contact-arms 0 one being carried by and insulated from one member of each of the switch-keys c c c 0 A normally open contact 0 is provided for each of the arms 0 said contacts 0 being connected by conductors 7 7 7 7 with a conductor 8,

The conductors 3 i of the leading to earth through the polarized mag-- net 11 ofthe converter E, a branch 9 leading 'fiom conductor 8 to, the vibrating arm eof the pole-changer E, "which is adapted to be operated by magnet d. The moving arm e -outer armae c of the ole-changer. Conto conductor 12.

tact members e e of t e pole-changer are normally mounted with their free ends lying between contacts 12 e and contacts 2 e, re-

spectively. Contact 6 of the pole-changer is .connected by conductor 1 1 with the opposite outer contacts 0 c ofv keys 0 0 respectively, while contact e isconnected by conductor 12 with opposite outer contacts 0 c of keys 0 a, respectively, the remaining or opposite outer contacts of said keys being grounded.

The arm 6 of the pole-changeris ada ted when 0 erated by the armature d to a ternately c ose contacts e 6 and e 6 according as the differently directed or alternating waves of current pass through the magnet d, so that pulsations of one character-for example, ositivewill be applied to conductor 11, w e pulsations of opposite character that is, of negative olaritywill be applied hus when the operator after plugging into the party-line desires to si na-l a station thereonfor-example No. Il she depresses key 0, whereupon limb 2 of the line is grounded and a circuit 5, 6, 7, and 8 is provided for the magnet 61 of the converter. Thfe pole-changer is now operated and negative pulsations applied to limb 1 by way of conductor 12, contact 0, and conductor 3, whereupon the bell at station II is operated in the usual manner.

A conductor 13 may lead from conduct-or 5 to the outer contact of the alternating ringin -key c", said conductor preferably including the usual resistance-lamp. The conductor 9 may also contain a resistance-lamp, if desired.

I also provide a synchronizer in the circuit 8/ adapted to maintain the pole-changer in tune with the alternating current. This synchronizer preferably comprises a condenser C, which serves to counteract any self induction or reactance in magnet d.

I claim- 1. The combination with a party telephone-line extending from two substations to a central office, of signals at said stations responsive to positive and negative pulsating current, respectively, a conductor at the central office carrying alternating current, an electromagnetically operated pole changer, adapted to separate said alternating current into positive and negative pulsations, means for operating said pole-changer, and switchmg devices at the central ofiice for applying pu sations of either character to the line.

2. The combination with an electric circuit containing signals responsive to positive and negative pulsating current, respectively, of a source of a ternating current, a olechangeradapt'cd to separate current rorn said source into positive and negative ulsations, a polarized electromagnet a apted when supplied with current from saidsource to operate said pole-changer, and switching mechanism adapted when operated to connect said source with said magnet and polechanger, an'd to apply pulsations of either character'to said circuit.

3. The combination with a party telephone-line extending-from two substations to a spring-jack at a central oliice, of signals at the substations responsive to positive and negative pulsating current, respectively, a conductor at the central office carrying alternating current, a plu and plug-circuit for making connection with the spring-jack of said line, an electromagnetica y operated pole-changer at the central oflice for separating said alternating current into positive and negative pulsations, and switches in said plugcircuit adapted when operated to connect said conductor with said pole-changer to operate the same, one switch being also adapted to apply positive and the other negative pulsations to the line.

4. The combination with a party telephone-line extending from two substations to a spring-jack at a central oflice,-of signals at said stat-ions responsive to positive and negative pulsating current, respectively, a conductor at the central o'fiice carrying alternating current, a pole -changer adapted to separate said alternating current into positive and negative pulsations, a plug and plugcircuit for .making connection with said spring-jack, mechanism for operating said pole-changer, and switch-keys atthe central oiiice controlling said mechanism and adapted to apply pulsations of either character to the linev 5. The combination with a main electric circuit, containing signals responsive to'pulsating current, of a source of alternating current, a circuit therefor, mechanism adapted to separate current from said source into positive and negative pulsations, a polarized magnet in said alternating-current circuit adapted to operate said mechanism, means for maintaining said mechanism in tune with the alternating current, and means for ap-' plying said pulsations to said main circuit.

6. The combination with a main electric circuit, containing signals responsive to positive and negative pulsating current, respectively, of a source of alternating current, a pole-changer adapted to separate alternating current from said'source into positive and negative (pulsations, a polarized electromagnet in sai alternating-current circuit, adapted to operate said pole-changer, a condenser in said circuit adapted to maintain the polechanger in tune with the alternating current, and means for applying pulsations of either character to the main'circuit.

7. The combination with a main exchange,

' extending from two substations eee eve of a private exchange, a party telephone-line to said private exchange, signals at said. substations responsive to positive and negative pulsating currents, respectively, a source of alternating current at tiiemain exchange, a conductor leading'from said souree to the private exchange, electromagnetically-operated mechanism at the private exchange edapted'to to separate the alternating current carried by I said conductor into positive and negative pulsations, and means for ap lying pulsetions of either character to the ine.

In witness whereof I hereunto subscribe my name this 30th day of January, A. D. 15 

